Flat roofing private house roofing roof. Flat Roof House Projects

During the construction of urban high-rise buildings and industrial facilities, a reinforced concrete slab usually becomes the basis of a flat roof. But for private houses, especially frame and wooden ones, this choice is most often unacceptable. In this case, a flat roof is built on wooden beams. Its main advantage is its light weight, which reduces the load on walls and foundations.

The device of such a roof is simpler and cheaper than when using heavy reinforced concrete slabs. But the functionality is the same. Therefore, this option of a flat roof is often chosen by those who want to build it with their own hands.

The main share of such roofs falls on private houses and cottages, whose owners appreciate the futuristic style, convenience and practicality. Still - on the floors of verandas, terraces, balconies, garages. As a rule, all these buildings are wooden or frame, requiring a light roof structure. But this is not a mandatory rule. The wall material can be any - brick, aerated concrete, foam concrete, etc. In this case, wooden beams often cut into a Mauerlat - a wooden beam that runs along the perimeter of the walls and is connected to them with anchor bolts or studs.

A flat roof is especially attractive to developers because its horizontal surface can be used as a usable area. Moreover, this is possible even for the roof, which is based on wooden beams.

Of course, you should not use the freed meters for a parking lot, a swimming pool or a tennis court. Still, such projects require a more monumental foundation. But an open terrace, an observation deck, a home greenhouse, wooden beams can easily withstand. The main thing is to correctly calculate and not save on the thickness of the lumber.

Types of flat roofs on beams

On wooden floors, you can build a flat roof of the following types:

• unexploited;
• exploited;
• inversion.

That is, all possible types - without restrictions.

Unexploited roof- ordinary, ending with a waterproofing finish. It is intended solely to protect the premises from environmental conditions and has no other purpose. It is impossible to use it as a place of rest, to move in large companies, to install terrace furniture and flowerpots. The coating of such a roof is designed for the fact that 1-2 people will periodically climb it, solely for the maintenance of the structure.

exploited roof- more interesting and more difficult. In addition to direct protective functions, such a roof plays the role of an additional usable area for the homeowner. The construction pie ends not with waterproofing (prone to damage), but with a protective coating - paving stones, decking, wood decking, paving slabs, sod layer, crushed stone or gravel.

inverted roof- roof-reversible, a qualitatively different option. It can be both operated and non-operated. Its feature is the inverted order of the layers in the cake. If in a conventional roof the waterproofing is laid on top of the insulation, then in the inversion roof the opposite is true. Waterproofing lies under the insulation, and vapor barrier is generally excluded from the structure of the pie. Due to this, the waterproofing is protected from the outdoor environment and its service life is increased.

However, under the influence of unfavorable outdoor conditions, there is a heater, therefore, as part of inverted roofs, the choice of this type of insulation is limited. Only EPS (extruded polystyrene foam) and nothing else! This material has almost zero water absorption, high density and strength. From above, EPSS in inverted roofs is loaded with washed gravel, paving stones, paving slabs or a sod layer.

An interesting option for operated roofs (including inversion ones) is green roof. It can also be held on wooden beams. The cake of such a roof ends with a soil layer on which plants are planted. There are other elements that are not used for other types of roofs: a drainage layer (gravel, expanded clay, crushed pumice or geomats), a filtration layer (geotextile).

Flat roof frame on a wooden base

The frame of the described roofs are wooden beams, laid according to the type of interfloor overlap. Full-length sawn wood or multi-piece (glued) timber can be used. Often beams are made of boards with a section of 100x150 mm.

Beams are laid with support on the walls, similar to interfloor ceilings. If the building is wooden or frame, then the beams rest on the upper crown of logs or the upper trim. If brick or block - then on a pre-fixed Mauerlat. As a Mauerlat, a bar with a section of 150x150 mm or 150x100 mm is usually used. It is mounted on the upper belt of the walls using anchors or studs. To protect the wooden Mauerlat from the material of the walls, 1-2 layers of waterproofing (roofing material) are laid between them.

On the beams, cuts are made under the Mauerlat, they are laid and fixed with metal corners or nails. The step between the beams is maintained 50-120 mm (depending on the calculated load).

When installing beams, it is important to ensure a roof slope of 1-6 °. Despite the fact that the roof is called flat, it is not absolutely horizontal. A slight slope is necessary to ensure the movement of water to the drain and thus prevent its stagnation.

You can create the required slope in the following ways:

1. Immediately lay the beams with the desired slope. Then, if a horizontal ceiling is supposed to be installed under the roof in the room, it is made suspended or sewn onto a horizontal crate.
2. Lay the beams horizontally, and to maintain the required angle, nail wooden plates of different heights to them.
3. Lay the beams horizontally, and form the corner due to the different thicknesses of the thermal insulation laid on top of the frame.
4. Use beams with unequal height allowance.

Most often, the first option is used, that is, beams with a slope are immediately laid. The easiest way to do this is to attach a strong beam or board run along the top of the load-bearing wall, which will raise the frame (beams) on one side. Instead of a cross purlin, you can also install short radial beams extending from the central double diagonal beam.

Flat roof pie: what's inside?

A flat roof cake on a wooden frame can have a different structure. There are many design options, many of them are posted on the Internet. And they will all work!

Option 1. Roof with insulation over beams

Flat roof insulation layers can be laid over the beams. For example, a proven working option (classic roof with insulation):

• floor beams;
• vapor barrier;
• waterproofing material - polymer membrane.

When using EPPS insulation and PVC membranes in the structure at the same time, a separating layer (geotextile, fiberglass) must be laid between them. The matter is that these two materials are incompatible and at their direct contact there is a destruction of PVC.

The polymer membrane is fixed on the insulation by a mechanical method or loaded with ballast. Crushed stone or gravel (for all types of roofs), paving stones (for operated roofs), soil (for green operated roofs) are used as ballast. However, when choosing a ballast, one should soberly assess the reliability of a wooden frame, its ultimate load.

If the use of welded-on waterproofing or an EPDM membrane with adhesive fixation is supposed to be used as a finish coating, a change is made to the scheme discussed above. It consists in the fact that sheets of plywood, OSB or DSP are laid between the insulation and waterproofing.

It turns out such a scheme:

• floor beams;
• crate (if necessary);
• solid sheathing made of plywood, DSP, OSB;
• vapor barrier;
• insulation - EPPS, mineral wool;
• sheets of plywood, OSB, DSP;
• waterproofing material.

The installation of built-up roofing traditionally requires the use of a gas burner, therefore, according to existing fire regulations, it is unacceptable on wooden structures. Therefore, they act as follows. The first layer of waterproofing is nailed or glued to a wooden base, and the second layer is fused, as it should be. It is also convenient to use euroruberoid with a special adhesive base, for which cold installation is recommended without heating with a burner.

Installation of a membrane roof on a wooden base is shown in the video plot:

Option #2. Roof with inter-beam insulation

Another principle for assembling a flat roof pie is associated with laying insulation in the inter-beam space. This option is more convenient than the first if EPDM membranes with adhesive fixation or welded roofing are used as waterproofing.

The following roofing pie scheme is often used:

• floor beams;
• vapor barrier (between beams);
• insulation (between the beams);
• crate (if necessary);
• solid sheathing made of plywood, DSP, OSB;
• waterproofing.

In principle, a similar system is used in the formation of classical pitched roofs.

Option #3. Roof with internal insulation

In this case, sheets of plywood, OSB or DSP are sewn onto the supporting structure (beams), and waterproofing is laid on them. The remaining insulating layers of the roofing cake are sewn from the side of the room.

A draft ceiling (made of boards or sheet materials) is fixed on the beams, planks are screwed to it perpendicular to the supporting beams in increments of 40 cm. Styrofoam plates are placed between the planks, gluing them to mastic or glue. A vapor barrier film is sewn to the insulating layer. Close the insulating cake with a finishing ceiling.

Or you can go against all the "traditional" solutions and build an inverted roof on the beams. Due to the fact that the waterproofing will be covered with insulation, that is, protected from stress, exposure to oxygen, UV rays and precipitation, its service life is significantly increased.

When constructing an inversion roof, you can use the following scheme (from bottom to top):

• beams;
• solid crate;
• waterproofing;
• separating layer (when using a PVC membrane as a waterproofing);
• EPPS insulation;
• separating layer - geotextile;
• ballast, paving slabs, decking, etc.

The principle of inverted roofing is often used for green roofs. For example, you can do this:

What top coat to use?

The wooden base of a flat roof, along with its advantages, also has features with a minus sign. This is an increased fire hazard and low bearing capacity (compared to reinforced concrete slabs).

For waterproofing such a roof, it is desirable to use materials that do not require hot installation. Ideally - polymer membranes. When choosing built-on bitumen-polymer coatings (from a series of euroroofing materials), the first layer of material is mounted mechanically, and the second - by welding. In order to minimize the possibility of fire of structures during installation, it is recommended to use non-combustible DSP boards as a continuous sheathing (on which waterproofing is laid).

When constructing exploitable and ballast roofs, it should also be remembered that excessive load on a wooden base can be fatal. Therefore, if the bearing capacity of the beams used is low, light materials should be selected for the finish coating - decking, deck board, rubber paving slabs (rubber mats), etc.

For many, a flat roof is associated with urban high-rise buildings, faceless and monotonous. But we are ready to surprise you! A flat roof in a private house will be a pleasant discovery for you if there is not much snow in your area, but the winds are strong enough. The fact is that in winter all snow accumulations from such a roof will simply be blown away. And the main thing is that not a single strong hurricane will be able to tear off the roof, which simply does not exist! And before you opens up a whole ocean of possibilities that now you can build over your head: a cafe, a dance floor, a mini-garden and even a whole greenhouse!

The main thing is to know about all the intricacies of building houses with a flat roof, and everything will work out. And now we will reveal all the secrets.

• Such a roof is much smaller in area than the most gently sloping pitched roof. And this is saving on materials.
• Such a roof is being built much faster than a gable roof, and even more so a hip roof.
• Comfort and safety of all rafter works. You still need to manage to fall from such a roof!
• Convenient subsequent repair and change of roofing.
• Unlike a gable roof, the dismantling of the old flat roof is usually not needed - this is additional waterproofing and protection. The new pie is made exactly like the old one, which saves a lot of time and effort.
• The ability to use the roof as an additional useful area where you can set up a flower garden, make an open terrace and even build a greenhouse.
• The ability to install transparent roof elements (with careful waterproofing), and thus make a view of the night sky.
• Possibility to build a house of laconic architectural form. Minimalism is at the height of fashion!

And now for the pros and cons:

• Such a roof generously accumulates snow in itself. After all, now he has nowhere to roll, and the snow itself often causes leaks.
• On especially generous days, the snow will have to be removed mechanically, which often damages the roofing.
• The structure of the roof is becoming more complicated: now we need gutters, which, in addition to everything else, are clogged.
• The difference is that water drains from the pitched roof rather quickly (and it happens that it does get into the under-roof space). But on a flat surface, it generally stands!
  Monitoring the moisture content of the insulation and the general condition of the roof should be regular.
• But, despite the fact that much less building materials are needed for its arrangement than for a pitched roof, a flat roof is much more difficult in terms of installation. Let's just say, there are a lot more different subtleties and nuances that are important to know about.

That is why many people have fair doubts about the reliability of such a roof. But the European and overseas experience of private residential buildings with a flat roof is successful, and therefore you can safely get down to business.

Consider only such points:

1. There is much more snow in Russia than in warmer European countries.
2. Worse than snow is only a big difference between summer and winter temperatures, which not all foreign roofing materials are designed for.

And here technology is everything!

What is a flat roof?

So, what acts as the supporting base of a flat roof:

1. Reinforced concrete slab.
2. Roof sandwich panels.
3. Reinforced steel sheet.

And thanks to the fact that they learned to make a flat roof “breathable”, i.e. with internal ventilation, it has now become possible to use completely non-breathing waterproofing - roofing felt like it.

Any roof that we call flat, in fact, still has a slight slope: to one side or purposefully towards the drainpipe.

Here is the simplest example of a flat roof for a private house:

Types of flat roof: unexploited and inverted

Cheaper, of course, cost unexploited roofs. And exploited, which are correctly called "inversion", include additional materials.

A separate type of flat roof of a residential building is exploited. Those. the one on which people will walk and what objects will stand. This is the same garden, or sports ground, or summer cafe. All this creates considerable loads on the roof, and therefore its device is already different from the one that is intended only to protect the house from precipitation.

So, the main difference in the arrangement of traditional and inverse roofs is that in the first layer of thermal insulation is under the waterproofing, which is quite logical, and in the second - above it. But in the second version, the waterproofing is more protected from ultraviolet rays and temperature extremes. This design is more durable and functional: you can safely arrange a lawn or lay paving slabs on it.

And now in more detail.

Unexploited roof: standard pie

But a person can also occasionally climb onto an unused roof - for the same repair, for example.

Those. in a traditional flat roof, the top layer is waterproofing, and it is she who is subjected to all mechanical and thermal stresses.

Its separate type is a roof with a pressure layer, which is designed for the fact that a person can walk on it from time to time:

Inversion Roofing: Reverse Pie

The standard slope of an inverted roof is 5-7%. The inversion method assumes that the thermal insulation layer is already located on top of the waterproofing, which now also serves as a vapor barrier.

Moreover, the cake of inversion flat roofs can be very different. It all depends on what you are going to arrange on the roof: a terrace, a mini-pool (and this is not uncommon) or a garden. But the foundation will still be common: a monolithic screed is made that levels the entire surface, then waterproofing is laid and all this is covered with insulation. And on top already - a cement-sand mixture or a rubber coating.

Note that the active operation of the roof is frequent damage to the insulating layer, due to which moisture makes its way to the insulation and freezes in winter. Over time, the entire roofing cake deteriorates, and therefore a flat roof cannot do without a ventilation system.

The cement-sand screed is able to distribute the pressure layer on the heat insulator even better, but it must be additionally reinforced with a cracking mesh.

The subtleties of flat roof insulation

A layer of thermal insulation for a flat roof is required. For comparison: a gable roof is insulated only when a residential attic is equipped under it, and in all other cases, a maximum of mineral wool is laid on the floor of the attic. But for a flat roof, insulation is always necessary.

The fact is that without a heat-insulating layer in a flat roof, condensate will constantly appear on the ceiling in the house (such a roof will just turn out to be the cold part on which water vapor rushes). And this is bad not only because it will have to be repaired, but also because the whole structure deteriorates in this way.

You can insulate a flat roof both from the outside and from the inside - the difference is small. More importantly, in how many layers a particular roof needs to be insulated - in one or two.

Heat-insulating materials must be fixed to the base of the roof mechanically, both with screws or dowels, and with glue. Sometimes the mount is not used at all if the heat insulator is located outside, and paving slabs or pebbles press on it.

Why two layers? The fact is that the first layer of thermal insulation on a flat roof performs the function of a heater, it is from 70 to 200 mm thick. And the second, from 40 to 50 mm, is designed to distribute all the loads. And it is important to calculate the thickness of both layers accurately, based on the climatic features of the area and the future use of the roof itself.

With two-layer insulation, all joints should go apart, in a checkerboard pattern, so as not to fall on each other. Moreover, in the places where the plates adjoin the walls and the parapet, it is additionally necessary to make heat-insulating bumpers. The cement-sand screed is able to distribute the pressure layer on the heat insulator even better, but it must be additionally reinforced with a cracking mesh.

Proper drainage system

But this is already a difficult task. Flat roofs are just bad because they are completely open to rain. But everything is solved! The main thing is to properly organize the drain, and for convenience, we have revealed this issue for you in such schematic illustrations:

Internal ventilation device

Another important point in the arrangement of flat roofs is ventilation. The fact is that if moisture randomly enters the insulation, it no longer evaporates - it only accumulates. As a result, the heat-insulating material rots, and the waterproofing swells. And there are many reasons for leaks: broken waterproofing, mechanical damage to the top layer of the roof, cracks and damage from frozen water.

A damp heat insulator is also bad because of it bubbles and cracks appear on a flat roof in the summer heat - all due to the active evaporation of water. As a result, the roof covering is also destroyed. And if moisture eventually gets under the old screed, then the entire roof begins to flake off. That is why a flat roof must "breathe".

For this purpose, so-called aerators are used on it. In appearance, these are simple plastic or metal pipes covered with umbrella caps. They should be placed evenly over the entire area of ​​​​the roof, preferably at its highest points. The essence of such a mechanism is that different pressures are created inside the roof and the air begins to create flows, along the way, taking with it all the excess moisture vapor.

In practice, it looks like this:

In addition, in any living space, water vapor rises up to the ceiling. Moreover, they often successfully overcome this barrier (the water molecule is quite small) and already get into the insulation, which is bad for him. That is why vapor barrier is required. And not the one that is usually used to insulate the attic, but dense, made of high-quality polypropylene or polyethylene. The bituminous membrane is even more reliable.

Choosing the right roofing

So, what is used as a coating for such roofs?

Option # 1 - bitumen and polymer-bitumen materials

Such roofs cost the owners of private houses the cheapest. Basically, we are talking about roofing material and euroroofing material. These are rolled roofing sheets, which are based on synthetic fabric, and on the sides are bitumen. As an elastic and frost-resistant material, bitumen serves as an excellent protection and waterproofing.

Moreover, the installation of bituminous roofing on a flat roof is absolutely simple, you only need a gas burner. The rolls are easily fused together.

But such a roof has a significant drawback - fragility. And also the fact that the roofing material does not breathe at all, i.e. vapor-tight, and therefore it is necessary to arrange ventilation for such a roof, unless you want the insulation to rot in a year:

Option #2 - liquid rubber

Such roofs have a huge advantage in that they do not contain any seams. As we have already said, the disadvantage of a flat roof is, first of all, that snow accumulates on it, which then causes leaks.

But there are subtleties here. So, liquid rubber for a flat roof should be taken only two-component, preferably the highest quality. And it is extremely important to correctly apply this material on a flat roof: evenly, avoiding unnecessary layers and savings in certain places. So, where the paint was applied unevenly, problems should be expected after 8-10 years.

Option #3 - PVC, TPO and EPDM membranes

Roofing membranes are valuable as flat roof coverings in that they allow steam to escape. After all, no matter what the vapor barrier used, moisture still at least a little, but gets into the insulation, not only from below, but also from above - after heavy rains, for example.

There are three types of membranes for the installation of such a roof: TPO, PVC and EPDM. The most popular is PVC membrane, it is also the most combustible. The EPDM membrane is more durable and affordable, but if mechanical damage occurs in it, nothing can fix it, while the PVC membrane is enough to melt with a hairdryer. In addition, the joints of the EPDM membrane must be glued with a special tape, which is much less reliable than the adhesion of PVC sheets.

But the cheapest membrane in its sector is PVC. But it has such significant disadvantages as low resistance to ultraviolet rays and fear of contact with bitumen, various oils and even polystyrene foam, otherwise the service life is significantly reduced.

Bonding EPDM membranes requires professional skills. TPO membrane, like PVC, is also hot air weldable. It is not afraid of the best ultraviolet, it is more chemically resistant and can be laid directly on polystyrene foam or old bituminous roofing without geotextiles. But its service life is shorter than that of EPDM, therefore, for the installation of a flat roof of a residential private house, we recommend using a PVC membrane.

So, the pie of a flat roof device with a PVC membrane is traditionally made like this:

• Step 1. We arrange a monolithic floor slab.
• Step 2. We put a tear-resistant vapor barrier film.
• Step 3. We make a ramp out of insulation or screed.
• Step 4. We put a heater. In private construction, this is usually foam with 35 density, and on top - XPS with 50 mm, which is even stronger.
• Step 5. Now geotextile, 300-500 g per square meter.
• Step 6. We turn to waterproofing - this is the PVC membrane. The density of the insulation is sufficient to walk on such a roof. But, if you plan to make an open terrace on the roof, then the cake needs to be continued further.
• Step 7. Lay the geotextile again - now directly on the membrane.
  We lay rubber tiles or reinforced screed 5-7 cm, on which we already lay paving slabs. To make a screed, you need ballast.

And such roofs are made of rubber, polymers or even foil. Unlike bituminous, they are durable, fire resistant and hold firmly to the base. They reach a slight slope with the help of expanded clay concrete or concrete screed.

How to achieve 100% waterproofing?

The main task when installing a flat roof is to make all joints and junctions as airtight as possible. After all, such a roof is most affected by moisture, hail, temperature changes and wind-blown debris. Therefore, the sealants used for sealing such joints must be of high quality and resistant to any influences. This is also a kind of expense that you have to go to.

For the same purpose of waterproofing, the slope of a flat roof is recommended to be at least 2%. Few? In fact, this is quite enough so that all atmospheric moisture does not linger on the surface, but flows down into funnels and pipes, and from them already into a septic tank, soil or sewer. Therefore, even at the design stage, you need to accurately think over the future drainage system.

Moreover, the drainage system itself is made both internal and external. So, the internal drainage system is a fitting - funnels located throughout the roof, which receive flowing water and direct it to pipes that go through buildings, but are isolated from living quarters. The only disadvantage of such a system is that the pipes are clogged with small debris and leaves, for which it is desirable to provide them with special filters and clean them periodically.

External drainage systems are already attached to the outer walls of the building. Of course, it is easier to clean such ones when they are clogged, but in cold weather they often freeze over. For which it is additionally customary to supply them with electrical heating in the form of cables.

As for the material for the internal and external drainage system of a flat roof, PVC or metal is quite suitable. Both options have their pros and cons. So, polyvinyl chloride does not corrode, but is more brittle than metal.

In order for the gutters not to freeze in winter, equip them with roofing thermal cables.

Green area on the roof: fashionable and environmentally friendly

Greenery and recreation areas are often not enough not only for the inhabitants of the "stone jungle", but even for the owners of private houses. The thing is that the same beautiful garden furniture is not always possible to leave in the courtyard of the house, and beautiful rare flowers in the garden flower bed are often trampled on by pets. Therefore, it is not surprising that the green area on the roof has become fashionable among the owners of cottages. Especially if the access to it goes immediately from the bedroom and no one else can disturb your morning peace with a cup of coffee.

There was also a fashion for some cafes to make the roof flat, and put a small greenhouse on it. All the greens - immediately on the table! And it’s profitable, because it’s not so easy to bring fresh dill or onions to the kitchen, and it’s economically profitable - there is where to send kitchen waste. And it's hard to know who borrowed this idea from whom: enterprising residents of private houses with a flat roof, or the best minds in catering. But the fact that such an arrangement of covered ground is beneficial is a fact: rodents will not dig under the beds, insects and pests will not get (as well as pests in the form of neighbors), and the fact that it is always a little hotter on the roof is only a plus for the same tomatoes. But the main thing is to correctly calculate the loads on such a roof during construction!

And the roofing pie often goes standard: waterproofing on the floor, thermal insulation, geotextiles, drainage and again geotextiles. And on top it is already possible both the earth and the beds:

Or in this version for more powerful overlaps:

A flat roof is a huge scope for any fantasy. Designers and architects love to bring to life a variety of projects for her: a garden, a greenhouse, a jogging track, a mini-beach with sun loungers, and much more. Some craftsmen even manage to make a parking lot on it!

A few centuries ago, a flat roof was considered a low-quality construction that starts to leak immediately after heavy rainfall, but today the situation has changed dramatically. A flat roofing system allows not only to reliably protect the building from atmospheric precipitation, but also to significantly save money. Of course, such a building will have its own nuances.

Flat roof structure

There is nothing complicated in the roofing layers of a flat roof. In fact, this is a multi-layer coating, which includes bituminous, polymeric and mixed products with a high level of waterproofing.

Depending on the functionality of the building and its purpose, the method of roofing is selected. Roofers know only two methods: fusing and pouring.

If you make a longitudinal section of the roofing carpet, then the following layers can be distinguished:

1. Waterproofing. Typically, this is the cover.
2. Cement-sand screed
3. Dense mineral wool boards
4. Vapor barrier layer
5. Reinforced concrete slab as a base

Now, I will paint each layer separately.

• As already mentioned, the role of waterproofing in most cases goes to the coating. It can be installed by welding, self-adhesive and pouring method. If we consider the first variety, then roll materials are used as materials, for example, roofing material or a membrane. As for bulk, the most common product of this type is liquid rubber and mastic.

If cheap roll material is used, then it is often stacked in several layers. This provides an increase in the durability of the product and good waterproofing of the plane. On flat roofs, it is advisable to lay up to 5 layers of rolled product. The average service life of roofing material is about 10 years, after which the surface must be covered with new material

• Cement-sand screed is not always arranged. Its filling is carried out only in the case of exploitation of the roofing surface. An example is houses in European countries, on the roofs of which there are gardens or recreation areas. This layer will give the surface additional rigidity, as a result of which the underlying materials will remain intact when exposed to loads.
• As a thermal insulation material, it is best to use mineral plates. In addition to its functional task, it performs functions similar to a screed and protects the inner layers from damage. It is worth noting that this layer should always be dry, otherwise moisture will play a cruel joke with it. The liquid that has got into the insulation plates significantly “cut off” its useful qualities and, having reduced them once, they will not return. Alternative material for flat roof insulation are: foam, basalt fibers or bulk products
• Vapor barrier material is an integral part of flat roofs. Thanks to them, the moisture coming from the living rooms through condensation will be blocked, therefore, it will not be able to reach the insulation boards.
• The base is most often reinforced concrete slabs and profiled metal sheets, but not so long ago an alternative was found - wood. If for a high-rise building, in which loads reach serious values, reinforced concrete elements are necessary, then for a small private house, a flat roof can also be laid on wooden beams. This design seriously saves your finances, and due to the small mass reduces the load on the foundation

The drainage system of flat roofs is a sore subject. It can be done both internally and externally. The first type has some advantages, but most developers prefer the second due to its simplicity and low cost. Despite the fact that the surface is flat, there are still slight slopes on it, this is called a slope. It is thanks to it that you can set the movement of precipitation.

It should be understood that these roofs should eliminate excess fluid without problems, otherwise the waterproofing material may give slack, and water will get inside and then you definitely won’t get out of an expensive repair.

IMPORTANT: If you are planning to lay welded-on products on a wood system, you should consider its flammability. Under such conditions, it is impossible to work with a burner, but how then to be? It will be necessary to fasten the first layer with ordinary nails, and only then carry out work in the usual way, using an open fire.

I will explain how to properly make a flat roof at home a little later, but for now I consider it important to understand its types.

Types of flat roofs

The structure of a flat roof roofing pie will differ significantly from its functional purpose. If wood or a reinforced concrete slab is used as a base, then you can afford an exploitable roof.

This is exactly the variety, the area of ​​\u200b\u200bwhich can be equipped at your discretion, but let's put everything in order.

• Unexploited roof. Laying its layers occurs in the traditional way. It lies in the fact that the waterproofing material is located above the thermal insulation slabs. Such an arrangement of the material does not allow even a person to withstand, therefore, to maintain such roofs, it is necessary to arrange bridges or ladders. As a rule, bulk products are used as a coating for such surfaces. Non-exploited roofing is suitable for temporary structures and outbuildings
• Operating roof. Here the structure of the roofing cake will be somewhat different. Thermal insulation boards are located above the waterproofing. They are made of dense material, such as mineral wool. Thanks to the screed located on top, the surface can withstand significant loads. On the surfaces of such roofs, it is possible to arrange not only recreation areas or a garden, but also swimming pools or parking lots. You just need to understand that for this you need to make additional calculations and acquire auxiliary materials. As a rule, when medium loads are planned for the exploited roof, paving slabs or other hard coating is laid on its surface. The method for laying layers of this roof will be called inversion

A building with a flat roof in most cases does not stand out for its beauty. Therefore, to increase these indicators, it is best to contact an experienced designer. He may advise you to decorate your comfort with a balcony or terrace. It is worth noting that the property of cheapness does not apply to the construction of operated roofs, but it will not differ significantly from the standard gable system.

Flat roof with wooden beams

A flat roof can be built with your own hands without any problems, because there is nothing false in this. To do this, it is enough to purchase the exact amount of material and acquire the necessary tools. By the way, despite the fact that all the work can be done independently, it is better to invite a partner. So the work will go safer and faster.

How to make a flat roof, you will learn from the points below.

1. First of all, it is necessary to take care of favorable conditions for construction. For most materials, weather between 5 and 25 degrees Celsius is optimal. As a rule, flat roofs are covered with bituminous products, therefore, this temperature range should not be ignored. The fact is that at negative temperatures, bitumen becomes brittle, and at very high temperatures it begins to melt.
2. After the erection of the walls, the support beam - the Mauerlat - is laid. It should fit on the upper belt, in which embedded parts are already inserted. They are needed so that the Mauerlat does not go along with the roof. In most cases, the material for the support beam is softwood lumber with a section of 15x15 centimeters. Reliable fasteners in this case are considered to be anchor bolts used in the absence of embedded parts, but it is not uncommon for these fastening methods to be combined with each other. Do not forget that Mauerlat is primarily wood, and it absorbs moisture very well, therefore, waterproofing is laid between the bearing wall and this element.
3. A flat wooden roof is laid from boards. They will serve as rafter legs, so their thickness must be at least 10x15 centimeters. In places where the support beam will pass, it is necessary to make a recess, which is half the height of the element itself. For example, if the height of the beam is 100 millimeters, then the recess will be 50. The step of the beams should be in the range from 60 to 120 centimeters. However, everything will depend on the roofing.
4. After working with the base and laying the vapor barrier layer, you can proceed with the installation of insulation boards. Most of the material has a width of 1.2 meters, therefore, their laying does not take much time. Glass wool, basalt fiber and slag wool are best suited for insulating flat roofs. This material is laid in several layers between the beams.
5. Before laying the roof covering, care must be taken to create a solid base and for this you will need moisture resistant plywood or wood flooring. If the roof is to be laid using the welding method, then the first layer is fixed with nails and planks, and only then a burner is used. Modern construction also has an alternative option - self-adhesive bitumen products, but it should be understood that the price for them is much higher
6. In most cases, a flat roof is designed to be exploited, and if you are pursuing the same goals, then do not forget about waterproofing the parapet. As a rule, roofing material is used as a material for this purpose. A special wedge is equipped at the junction of the vertical element and the roofing plane. It makes a sharp corner more rounded

I hope I have explained clearly how to make a flat roof with your own hands, but if you cannot understand any of the details, contact the experts. They will not only tell you how to lay the roof, but they can also provide their services.

Do-it-yourself flat roofing is a great way to build a building in a very short period of time and at the same time save a lot of money.

But do not forget that self-laying should include a complex for protecting both materials and the building itself.

For example, in the first case, antiseptics, various paint and varnish products, and the like can be used, but the second will require a more thoughtful approach, because fire safety is an important component of all construction.

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In European countries, flat-roofed houses, which can be seen in the photo, are not uncommon; they are often built in the resort towns of the Mediterranean, since precipitation is an infrequent occurrence there. In domestic open spaces, buildings with such a roof are still rare, they mainly have an industrial or economic purpose - workshops, garages, repair shops, etc. The reason lies in the fact that property owners prefer classic projects for the construction of private cottages.

flat roof houses

The most common form of their construction is considered to be square houses with a flat roof, they are luxurious penthouses that attract the views of passers-by with their appearance.

Disadvantages and advantages of flat roofs

The advantages of flat roofs are obvious:

• it is possible to use the roof surface for your own needs, there you can arrange a place for recreation or sports, plant an ornamental garden, green lawn;
• it is profitable to build a house with a flat roof, since a significant amount is saved, which is necessary to create a truss structure;
• snow that accumulates on the roof surface in winter acts as an additional insulating layer (experts call this circumstance controversial);
• for the operation of the top coating in winter, you can install a heating system;
• if inexpensive roofing materials were used to create the roof, then a significant amount will not be required for the repair and it will be possible to do it on your own. In addition, repair work, if the roof is made, for example, of roofing felt, is not done on the entire surface, but only partially in case of overlapping defects.

The disadvantages include the following points:

• in the event of negligence or unprofessional construction work when creating a house with a flat roof, it may be necessary to repair the interior of the building, which will cost a lot of money. To reduce the likelihood of leaks, you must not forget about observing a slight slope of the roof, otherwise the precipitation will not drain, but will remain on it.

Taking into account the disadvantages and advantages of choosing flat roofs, we can conclude that this type of roofing is currently relevant and is a promising and reasonable solution, since it becomes possible not only to build an original building, but also save a significant amount of money.

Features of a flat roof device

The construction of houses with a flat roof has a number of nuances that should not be forgotten at the design stage. Most often, the basis for are corrugated board and reinforced concrete slabs, less often lumber is used.

The installation of corrugated board is considered the most economical and financially beneficial, but it can be used when the upper surface of the roof is not in use, in addition, additional insulation is required. Concrete is considered reliable and durable, since on top of it it is possible to install not only a gazebo for relaxation, but also a small swimming pool, which is used in summer.

A natural wood base is usually constructed when building frame houses with a flat roof.

Flat roof decking

If a house with a flat roof is being built using corrugated board, then after installing the support, a vapor barrier layer is laid on top of it. It is necessary to prevent heat loss from the interior of the building. The vapor barrier material is produced in rolls having a certain width and length. Places of overlapping vapor barrier, which can be used as a polyethylene film, must be carefully connected.

Then a heat-insulating layer is mounted using plates for insulation, which are joined together. For reliability, a two-layer laying system is often used. There are bulges on the sheets of corrugated board, which must be tightly filled with heat-insulating material.

After that comes the stage of creation using a polymer film. When all the insulating layers are laid, reinforced concrete slabs are mounted or a sand-concrete screed is poured.

When a country house with a flat roof is being built, regardless of what the base is made of, it is always necessary to make a slight slope - at least 5 degrees, otherwise water will remain on its surface.

Even a minor oversight made during the construction of a house with a flat roof can cause a major overhaul in the very near future.

Flat roof waterproofing and insulation

Brick or wooden houses with a flat roof require high-quality waterproofing of the roof, which is performed using:

• films to create a protective waterproofing barrier against moisture;
• EPDM membranes, PVC membranes;
• hydrophilic rubber;
• liquid rubber - sprayed waterproofing;
• injection materials (silicone resins);
• lubricating compounds that are used to connect waterproofing sheets;
• penetrating materials.

Membrane insulation. It is considered an advanced technology that allows for high-quality waterproofing when a frame house with a flat roof is being built.

Diffusion membranes are in the greatest demand, they are:

• with microperforation;
• superdiffusion;
• anti-condensate.

Environmentally friendly and fireproof superdiffusion materials are especially in demand, since during their installation it is not necessary to leave a gap between the layers of waterproofing and thermal insulation, they repel moisture, preventing its penetration into the thermal insulation layer. The service life of such membranes is about 25 years. They are often used when building a wooden house with a flat roof.

There is another way - old and well-tested - this is adhesive waterproofing. It involves the use of roofing material, which is glued to the surface by heating.

flat roof insulation

Insulation of flat roofs is one of the very important types of work associated with. You can do it from the outside or from the inside in one or two layers. The easiest and cheapest way is to insulate the roof from the outside. The two-layer thermal insulation system makes it possible to reduce the load on the floors. The first layer is a heat insulator. The second layer is denser; the distribution function is assigned to it.

It is not difficult to create a flat roof with your own hands - the main thing is to follow the technology.

A house with a flat roof, in a row of the same type of "boxes" with a pitched roof, looks fresh and unusual. Therefore, every year the number of suburban residents who are seriously considering the construction of such a house for permanent residence is increasing. Fans of the "cubic" design are captivated by the wow effect and increased attention from the neighbors. Someone wants to place engineering equipment on the roof, or lay out a lawn and equip places for recreation. Still others believe that it is cheaper and easier to build a house with a flat roof than with a pitched one. Is it really? Consider the main pros and cons of these buildings and conclude whether they are suitable for our country. To do this, we will answer the following questions:

• Why is it difficult to choose a suitable plot for a "cubic" cottage
• Is it true that flat roofs are not suitable for our climate?
• Why is a flat roof leaking?
• A flat roof is simpler and cheaper than a pitched one - this is a myth
• Why flat roofs are difficult to repair

1. House with a flat roof and domestic realities

Most country dwellers look with skepticism at cottages with a flat roof, calling these houses “boxes”. Why? Flat roof houses came to us from abroad. Traditionally, they were erected in countries with a warm climate, where there is practically no winter, heavy snowfalls, severe frosts with sudden thaws, prolonged rains, but strong winds blow. For example, somewhere on the Mediterranean coast. Then these houses turned into a fashion design trend “not for everyone” in Western Europe, and from there they came to us.

Tretin FORUMHOUSE User

I see that we mainly build houses with pitched roofs. But, is it really necessary? In Germany and Switzerland, flat-roof house designs have long been offered. What can be the disadvantages of a flat roof, in addition to an imaginary unaesthetic appearance?

Indeed, can a cottage with panoramic windows in the photo below leave anyone indifferent?

Or such a high-tech house with a flat roof in the forest.

Or a cottage, on the roof of which an observation deck is made, a lawn is laid out and a place to relax is equipped.

Now imagine these houses with us. Harsh winter. In an ordinary - not an elite village, where roads float in spring and autumn, and plots are fenced with a profiled sheet. Houses in the mass are finished with siding or lined with facing bricks. And pitched roofs are covered with slate, metal tiles or, less often, a more expensive solution - shingles. The picture doesn't add up. Something is missing, isn't it? You no longer want to sit on the flat roof of the house, as you dreamed, with a cup of tea or coffee. After all, from there you can see not the ocean, sea, mountains or nature untouched by man, but dense rural buildings or, at best, fields overgrown with grass.

A house with a flat roof, in high-tech style, looks advantageous only on a spacious isolated area, for example, on a slope, with a beautiful view of the forest, lake or river. A cottage with a flat roof is lost without landscaping, and among solid, but the same type of houses, it looks like a "white crow".

This is where the first "pitfall" - dreams of a stylish house with a flat roof are broken when you realize,how much will the plot cost on which the cottage will look as it should.

Having conceived the construction of a house with a claim for a non-standard foreign design, select the appropriate site for it.

2. Reliability of a flat roof in our climate

When you look at beautiful houses that are hundreds of years old, ask yourself why they were built the way they were. Why do houses built in the coastal zone somewhere in Norway, Sweden or Scotland have no overhangs and the usual drain? They are simply not needed because of the strong winds that turn the rain into a horizontal stream of water hitting the walls. The same is true for houses with flat roofs. They were built in a warm climate, where there is little rainfall, but a strong wind load.

A flat roof is more wind resistant than a pitched one.

dmitrievich-50 FORUMHOUSE User

Our ancestors are smart people. They considered the design of the house in terms of practicality, based on the climatic conditions of residence. Why were flat roofs built in Central Asia? Are they pitched on the Central Russian Upland? In the Baltics, not just pitched, but with an acute angle of the ridge? A pitched roof with a slope of 45 degrees, in the Moscow region or in Saratov, will provide reliable protection from rain or snow for 20-25 years, even if covered with cheap corrugated board or slate.

A flat roof, with the right approach to construction and using modern materials, will also provide reliable protection for the house from precipitation and will not leak.

The only question is how much 1 sq. m of such a roof with a guarantee that it will not quickly leak with frequent transitions through 0. Icing. Nighttime freezing and daytime thawing of snow cover. Lingering downpours. And most importantly - how to make such a roof so that it serves for a long time in our climate?

The second difficulty in building a cottage with a problem-free flat roof is the harsh Russian operating conditions.

3. The main problem of building a reliable house with a flat roof in the Russian Federation

link82 FORUMHOUSE member

The company built a house with a flat roof for me. On the edges made 6 pcs. heated funnels and brought out to the sides, through the parapet, drain pipes. Is it correct? Maybe it was necessary to make a slope in the center and, with a small roof area, put two funnels instead of six? And let the pipe inside the building. Lead to the basement and further into the storm sewer? I am afraid that the knee, which is brought out of the funnel into the street, will freeze. Ice has already formed on the pipes. What if the pipe burst due to frost? How to fix it? Throw a heating cable? So much money has already been spent on this roof!

Flat roof house built in 2013.

In addition to problems with drainage, another one was added. When link82 I came to check the house, I found that the roof was leaking in several places. Water went from the second floor to the first. The whole drywall floated. Now you have to swear with the builders. Trying to take the money, and completely redo the roof. According to Michael-snabss(the portal user is professionally engaged in the construction of flat roofs) in this example, a whole bunch of errors have been collected. The main of which - builders who just don't know how to make flat roofs.

When building a house with a flat roof, do not chase cheapness. Each step of the builders and the stage of work needs strict control. More thorough than when erecting a pitched. Mistakes are costly!

The roof was most likely made of a built-up waterproofing material - stekloizol. The tree played and the fiberglass tore. Repair of this roof with a special roofing membrane will cost from 130 to 200 thousand rubles.

The third factor complicating the construction of a cottage with a flat roof in the Russian Federation - lack of highly qualified builders who know exactly how to build just such houses. How to use and combine materials with each other. What tools are needed for this. Even if the future owner of a flat roof house has a detailed project, and he should be, then everything can be spoiled by “specialists” working on the principle: “we always build like this and no one has complained yet!”.

Flat roofing should only be done by professionals.

4. Is flat roofing cheaper and easier than pitched roofing?

Usually, when it comes to the benefits of a flat roof, you can hear the argument that it is cheaper than a pitched one. Why? Less area - less material consumption. It is easier to make an overlap, because. no need for a classic truss system. There is no need to equip the attic floor, etc. And it's true, but as they say, the point is in the details.

If we simply consider the "pie" of a flat roof, then on the base, for example, concrete floor slabs, are laid:

• vapor barrier;
• thermal insulation;
• waterproofing.

Or the so-called. inverted flat roof where the layers go like this:

• waterproofing;
• thermal insulation;
• finishing layer.

In an inverted flat roof, the waterproofing layer is located under the insulation and “works” in more benign conditions, because. from above, from the negative influence of weather phenomena, it is protected by rubble, tiles or soil with a lawn. Those. a ballast flat roof is being installed.

But, when building a flat roof, it is necessary:

• Arrange slopes for water drainage - about 2 cm per 1 running meter. Slopes are usually made with a concrete screed or wedge-shaped insulation elements.
• Lay several layers of insulation. If stone wool is used rather than extruded polystyrene foam, install aerators to remove water vapor from the insulation.
• Put water intake funnels with electric heating, otherwise, due to the formed ice, they will not divert water from the roof.

One water intake funnel, 110 mm in diameter, drains water from an area of ​​up to 300 square meters. m.

• Install a downpipe with a slope of 3 cm per 1 running meter.
• Qualitatively make waterproofing from PVC, TPO or expensive EPDM membranes. TPO membranes are less elastic than PVC membranes, but have higher strength. Welding TPO membranes requires professional installers with special equipment. The advantage of EPDM membranes is the large format, and the fewer welds, the more reliable the flat roof.

When installing a flat roof, you will have to take into account many nuances.

Calculate the snow load depending on the region of residence. For example, Moscow and St. Petersburg belong to the third climatic region. Snow load on a flat roof, with a slope of 2%, in the Moscow region will be 180 kg per 1 sq. km. m. In the fourth climatic region, the snow load is 240 kg per 1 sq. km. m, and in the fifth already 320 kg. Do not forget that the weight of 1 m 3 of loose freshly fallen snow is on average 50 - 100 kg. Already caked 350 kg. A cube of wet or melting snow weighs approximately 400-600 kg.

With a properly calculated flat roof, snow does not need to be removed in winter. The excess is blown away by the wind, and loose snow becomes a heat insulator.

But, the load on a flat roof must be considered with a larger margin than on a pitched one, subject to force majeure circumstances. For example, the water intake funnels were clogged, the heating cable burned out, and the water did not leave the roof. For a couple of days, the monthly rate of snow fell, but there was no wind to blow it away and it lies on the roof. The additional weight on the roof puts pressure on the walls, which in turn transfer the load to the foundation, which redistributes it onto the subgrade. The further north, the greater the load. We will add a mass of crushed stone or soil with grass if a ballast flat roof is being arranged.

From here - the optimal design of a cottage with a flat roof is not a frame or a wooden house, but a stone building, calculated by the designer and built of aerated concrete, brick, warm ceramics, using monolithic technology. Because "cubic" design involves large unsupported spaces, then it will no longer be possible to block a span of more than 6 m with a tree. Trusses, I-beams, hollow core slabs, cast-in-situ slabs or prefabricated slabs are required. Do not forget to add expensive facade finishing solutions to the cost of a house with a flat roof.

You can't finish a house like this cheaply.

Planken, burnt wood, hand-molded brick, wet facade, combined facades made of wood and stone are used. And you can’t put standard windows in a house with a flat roof. Large or panoramic are needed. Add to this additional areas of parapets, which also need to be insulated and finished. This increases the cost of construction.

The fourth factor - a house with a flat roof cannot be called budget construction.

Consider the costs not only for the roof, comparing the final estimate with flat and pitched, but for the total cost of the entire “box” with the finish.

5. Low maintainability of a flat roof

sv2321 FORUMHOUSE User

I have a flat roof house. Waterproofing - membrane. I'm struggling with the roof. As they say, water will always find a hole. I like a flat roof, but I think I will abandon it and remake it with a pitched one, although I will have to change the entire architecture of the house. And that's why:

• There is no absolute guarantee that all flat roof joints will be airtight. Enough microcracks and gone. If there is a slope, then small defects are not critical;
• Snow lingers on a flat roof. He melts. Water fills microcracks. Frost struck at night. The water is frozen. With frequent daily freeze-thaw cycles, microcracks increase and then break. They are getting bigger. The pitched roof has no welded sections and there is nothing to tear there. In the most unfortunate case, there will be a small temporary leak without progressive consequences. It is easy to find and repair;
• The most annoying. On a flat roof, you will never know exactly where the defect has formed. A leak in one place, and water dripping from the ceiling in a completely different place. Masters will come, check the joints and find one of the defects, and the rest will remain. If the roof is inverted or loaded with gravel, then troubleshooting is an even bigger problem.

According to the user, the optimal roof for our climate is pitched. The angles at the slopes compensate for the crooked hands of the builders and the change in the properties of materials over time, and the overhangs protect the walls and finishes from precipitation.

So, fifth - low maintainability. The quality of a flat roof is greatly influenced by the human factor.

If a pitched roof with a cold attic is leaking, then it is not difficult to find and repair a defective area. In extreme cases, you can dismantle the coating and perform local repairs or get close to the problem area from the inside. In the case of a flat roof, leak detection and repair is made more difficult by the complex pie. Many layers in the design, especially in the so-called. "green roof". The presence of a concrete screed, etc.

findings

Houses with a flat roof certainly look beautiful and stylish. Make a flat, hassle-free roof that will last for many years in our climate also possible. The only question is the total cost of all decisions and its expediency. Anyone who has been involved in the installation or repair of roofs in our climate knows that in summer, the sun-hot roof is the last place where you would like to sit with your family or friends. Hot and stuffy. I would like to quickly go into the shadows. If there are small children in the house, then an exploited flat roof is an extra headache for parents. You can also organize a shaded private place to relax with barbecue on a small area. Sunbathing is pleasant in the garden on the grass, throwing a towel or spreading out a deck chair, and not in front of all the neighbors and passers-by on the roof. The suburbs simply want solitude, and not stick out their private lives for everyone to see. Let's add our changeable weather. Rain. The wind, which at a height is felt quite differently than below. In total, how many days a year will really be left to relax on a flat roof? Let's add the need to arrange a place to go to the roof directly from the house. Do not climb onto a flat roof along the stairs, which are fixed on the facade. What's left? Unusual "fashionable" design to attract attention. Therefore, whether to build a house with a flat roof or not, let everyone decide for himself, and FORUMHOUSE offers you proven solutions for this.

• how to build a house in our climate with a roof without overhangs with a hidden gutter, and what are its advantages.

Stone house with a flat roof: a harmonious combination of exterior and interior. In the video - the design features of a monolithic stone house with a flat roof and an unusual facade finish.